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Content available remote A method for sensor placement taking into account diagnosability criteria
100%
Yassine A. , Ploix S. , Flaus J.-M.
International Journal of Applied Mathematics and Computer Science
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2008
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tom 18
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nr 4
497-512
EN
This paper presents a new approach to sensor placement based on diagnosability criteria. It is based on the study of structural matrices. Properties of structural matrices regarding detectability, discriminability and diagnosability are established in order to be used by sensor placement methods. The proposed approach manages any number of constraints modelled by linear or nonlinear equations and it does not require the design of analytical redundancy relations. Assuming that a constraint models a component and that the cost of the measurement of each variable is defined, a method determining sensor placements satisfying diagnosability specifications, where all the diagnosable, discriminable and detectable constraint sets are specified, is proposed. An application example dealing with a dynamical linear system is presented.
2
Content available Effective sensor placement based on a VIKOR method considering common cause failure in the presence of epistemic uncertainty
88%
Duan R.-X. , He J.-J. , Feng T. , Huang S.-J. , Chen L.
Eksploatacja i Niezawodność
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2021
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tom Vol. 23, no. 2
253--262
EN
Owing to expensive cost and restricted structure, limited sensors are allowed to install in modern systems to monitor the working state, which can improve their availability. Therefore, an effective sensor placement method is presented based on a VIKOR algorithm considering common cause failure (CCF) under epistemic uncertainty in this paper. Specifically, a dynamic fault tree (DFT) is developed to build a fault model to simulate dynamic fault behaviors and some reliability indices are calculated using a dynamic evidence network (DEN). Furthermore, a VIKOR method is proposed to choose the possible sensor locations based on these indices. Besides, a sensor model is introduced by using a priority AND gate (PAND) to describe the failure sequence between a sensor and a component. All placement schemes can be enumerated when the number of sensors is given, and the largest system reliability is the best alternative among the placement schemes. Finally, a case study shows that CCF has some influence on sensor placement and cannot be neglected in the reliabilitybased sensor placement.
3
Content available Exact and approximation algorithms for sensor placement against DDoS attacks
75%
Junosza-Szaniawski K. , Nogalski D. , Rzążewski P.
International Journal of Applied Mathematics and Computer Science
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2022
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tom Vol. 32, no. 1
35--49
EN
In a distributed denial of service (DDoS) attack, the attacker gains control of many network users through a virus. Then the controlled users send many requests to a victim, leading to its resources being depleted. DDoS attacks are hard to defend because of their distributed nature, large scale and various attack techniques. One possible mode of defense is to place sensors in a network that can detect and stop an unwanted request. However, such sensors are expensive, as a result of which there is a natural question as to the minimum number of sensors and their optimal placement required to get the necessary level of safety. Presented below are two mixed integer models for optimal sensor placement against DDoS attacks. Both models lead to a trade-off between the number of deployed sensors and the volume of uncontrolled flow. Since the above placement problems are NP-hard, two efficient heuristics are designed, implemented and compared experimentally with exact mixed integer linear programming solvers.
4
Content available remote A method for sensor placement taking into account diagnosability criteria
63%
Yassine A. A. , Ploix S. , Flaus J.-M.
International Journal of Applied Mathematics and Computer Science
|
2008
|
tom Vol. 18, no 4
497-512
EN
This paper presents a new approach to sensor placement based on diagnosability criteria. It is based on the study of structural matrices. Properties of structural matrices regarding detectability, discriminability and diagnosability are established in order to be used by sensor placement methods. The proposed approach manages any number of constraints modelled by linear or nonlinear equations and it does not require the design of analytical redundancy relations. Assuming that a constraint models a component and that the cost of the measurement of each variable is defined, a method determining sensor placements satisfying diagnosability specifications, where all the diagnosable, discriminable and detectable constraint sets are specified, is proposed. An application example dealing with a dynamical linear system is presented.
5
Content available remote Using relay nodes in wireless sensor networks: a review
63%
Senouci M. R. , Zafer M. , Aissani M.
Annals of Computer Science and Information Systems
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2019
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tom Vol. 18
479--486
EN
To extend the lifetime of wireless sensor networks, recent works suggest the use of relay nodes. This paper surveys and examines representative approaches dealing with relay nodes deployment. It also discusses their shortcomings and presents a comparative study. Additionally, this paper provides a set of remarks and recommendations to improve the usage of relay nodes in wireless sensor networks and highlights open issues that need further investigation.
6
Content available remote Source localization and sensor placement in environmental monitoring
51%
Khapalov A.
International Journal of Applied Mathematics and Computer Science
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2010
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tom Vol. 20, no 3
445-458
EN
In this paper we discuss two closely related problems arising in environmental monitoring. The first is the source localization problem linked to the question How can one find an unknown 'contamination source'? The second is an associated sensor placement problem: Where should we place sensors that are capable of providing the necessary 'adequate data' for that? Our approach is based on some concepts and ideas developed in mathematical control theory of partial differential equations.
7
Content available remote Exact and approximation algorithms for sensor placement against DDoS attacks
51%
Junosza-Szaniawski K. , Nogalski D. , Wójcik A.
Annals of Computer Science and Information Systems
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2020
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tom Vol. 21
295--301
EN
In DDoS attack (Distributed Denial of Service), an attacker gains control of many network users by a virus. Then the controlled users send many requests to a victim, leading to lack of its resources. DDoS attacks are hard to defend because of distributed nature, large scale and various attack techniques. One of possible ways of defense is to place sensors in the network that can detect and stop an unwanted request. However, such sensors are expensive so there is a natural question about a minimum number of sensors and their optimal placement to get the required level of safety. We present two mixed integer models for optimal sensor placement against DDoS attacks. Both models lead to a trade-off between the number of deployed sensors and the volume of uncontrolled flow. Since above placement problems are NP-hard, two efficient heuristics are designed, implemented and compared experimentally with exact linear programming solvers.
8
Content available Application of an memetic algorithm to placement of sensors for active noise-vibration control
51%
Wrona S. , Pawełczyk M.
Mechanics and Control
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2013
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tom Vol. 32, no. 3
122--128
EN
For successful active control of a vibrating structure it is essential to appropriately place sensors. One of the most important criteria is to make the system observable, so any control objectives can be achieved. In this paper the observability-oriented placement of sensors is undertaken. First, a theoretical model of a fully clamped plate is presented. Optimization criterion based on maximization of observability of the system is developed. A memetic algorithm is used to find the optimal solution. Obtained results are compared with those obtained by the genetic algorithm.The configuration is also validated experimentally.
PL
W celu skutecznej aktywnej redukcji drgań i hałasu konstrukcji konieczne jest odpowiednie rozmieszczenie czujników. Jednym z najważniejszych kryteriów jest uczynienie obiektu obserwowalnym, aby jakiekolwiek cele sterowania mogły zostać osiągnięte.W pracy podjęte zostało zagadnienie rozmieszczenia czujników w oparciu o analizę obserwowalności. Zaprezentowany został model teoretyczny płyty o brzegach całkowicie utwierdzonych. Wyprowadzone zostało kryterium optymalizacji w oparciu o maksymalizacje miary obserwowalności. Do znalezienia rozwiązania optymalnego zastosowano algorytm memetyczny. Otrzymane wyniki zostały porównane z wynikami uzyskanymi za pomocą algorytmu genetycznego. Wyznaczone rozmieszczenie czujników zostało zweryfikowane eksperymentalnie.
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